V$SGA

Oracle 11gR1

V$SGA displays summary information about the system global area (SGA).

Column	Datatype	Description
NAME	VARCHAR2(20)	SGA component group
VALUE	NUMBER	Memory size (in bytes)

Note:

Use the following query to see the contents of SGA:

select * from v$sga order by name;

NAME	VALUE
Database Buffers	12918456320
Fixed Size	2059120
Redo Buffers	14712832
Variable Size	4244640912

If you are migrating from a manual management scheme, execute the following query on the instance running in manual mode to get a value for SGA_TARGET:

select (

(select sum(value) from v$sga) –

(select current_size from v$sga_dynamic_free_memory)

) "SGA_TARGET"

from dual;

The following views provide information about the SGA components and their dynamic resizing.

View	Description
V$SGA	Displays summary information about the system global area (SGA).
V$SGAINFO	Displays size information about the SGA, including the sizes of different SGA components, the granule size, and free memory.
V$SGASTAT	Displays detailed information about the SGA.
V$SGA_DYNAMIC_COMPONENTS	Displays information about the dynamic SGA components. This view summarizes information based on all completed SGA resize operations since instance startup.
V$SGA_DYNAMIC_FREE_MEMORY	Displays information about the amount of SGA memory available for future dynamic SGA resize operations.
V$SGA_RESIZE_OPS	Displays information about the last 400 completed SGA resize operations.
V$SGA_CURRENT_RESIZE_OPS	Displays information about SGA resize operations that are currently in progress. A resize operation is an enlargement or reduction of a dynamic SGA component.
V$SGA_TARGET_ADVICE	Displays information that helps you tune SGA_TARGET.

Oracle dynamic performance views